Volvo Penta -Saildrive diaphragm and Engine oil leak

[skipperpete]

My phone had trouble with the VPSHOP link but here’s a pic from the service manual.
Importantly, the leaking seal might be only a symptom so before opening up the top case, check the input shaft for movement , it should only rotate..... no end float or lateral movement is permitted. Also take a close look at the drive plate in the flywheel housing, it can also be problem. [ATTACH]268352
You will need to move the engine forward to get the input shaft out of the drive plate and yes it’s best to lift the lid off and then take the shaft out to install that seal. Don’t lose or damage the shim sets.

[Ohanapaavandet]

Originally Posted by skipperpete

Importantly, the leaking seal might be only a symptom so before opening up the top case, check the input shaft for movement , it should only rotate..... no end float or lateral movement is permitted. Also take a close look at the drive plate in the flywheel housing, it can also be problem. [ATTACH]268352
.

Thanks for the reply @skipperpete.

Can you elaborate on the part about the "drive plate". How is that a potential source of transmission oil leak? What am i looking for and would'nt that be more of a source for engine oil leak ?

I have (tried at least) to attach the exploded view of the block and flywheel housing and the drive plate we are talking about is part nr. 28 on the view correct or am I misunderstanding?

Getting to that plate would reguire me to take of the flywheel housing of the engine and I would love to not have to do that, but keep the operation to the sail drive, if possible - hence my follow questions

Thanks again

[skipperpete]

The drive plate ( damper plate) connects the flywheel to the gearbox input shaft via a floating splined hub and if the springs ( or polymer) that support that hub collapse and the load becomes a combination of axial and lateral then the input shaft bearing cops a flogging and the seal is often the first indication of a problem. Just do a visual inspection of it and the condition of the splines in both the hub and the input shaft. In your parts diagram the damper plate, 34, appears to be the polymer one so look for bits of broken plastic

[DougR]

As Pete says, the damper plate is item 34, and it is a rubber/ polymer two stage damper. Depending on the vintage of your engine you might be able to remove the damper without removing the flywheel housing. Earlier models of the engine had flywheel housings with a full circle pilot opening for the saildrive/ transmission mounting. These engines required the removal of the housing to remove the damper. Later engine models had “notches” in the flywheel housing opening which allowed the mounting ears of the damper to pass thru the opening and allowed removing the damper with the flywheel housing in place. A close look at the parts breakdown which you attached will show the mounting ears on the damper and the notches in the flywheel housing.